Mike Matthews has torn patellar tendon

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When the Steelers waived center Mike Matthews with the injury designation, his specific injury wasn’t known. It now is.

Per a source with knowledge of the situation, Mathews suffered a torn patellar tendon. He’s expected to be out for 4-6 months.

Matthews, if unclaimed on waivers, will revert to Pittsburgh’s injured reserve list. He’s the son of Hall of Fame offensive lineman Bruce Matthews.

The Steelers signed Lucas Crowley to take Matthews’ spot on the roster. Matthews was an undrafted free agent in 2016, signing with the Browns.